How to get album cover for all songs in Android mobile?

Sometimes songs are downloaded from websites, songs will not contain any album cover or picture. While you open your music player these songs will not be associated with any picture and some default icon will be present. Check out the below screenshot where couple of songs doesn't contain any album cover and some default icon is present instead.

Fix it in 3 steps

1. Download and install Cover Art Grabber from playstore
2. Open cover art grabber application 
3. Click "fetch missing cover" and it fetches all album covers in background

Next time when you open your music player you will find album covers for all the songs. In case, if some covers are missing. You can search for that particular song through this application. Every song you download will have some metadata associated with it. Metadata contains information like song name, album name , artist name etc. If this information is not correct then you will not be able to fetch proper album cover for those songs. To fix those metadata , you can use "iTag" option in this application. Currently this option doesn't seem to work in this application. I have reported this to the developer and hope he fixes it ASAP. Until then you can use an alternate application called  "iTag - music tag editor".  iTag app can also be used to search and pick cover pictures. Both the applications are free and contains ads in it.